Hey, this problem has been happening to me for a several months. Only now have I decided to seek outside help for it. So ever since the new interface update I have been unable to connect to connect to a specific friend's party or game invites. He cannot connect to mine either. I've tried many things such as testing my NAT (its open), I've restarted my router and modem several times and he's done the same, I un-friended him and then re-friended him and that didnt work. I've tried connecting on another Xbox in my house and that doesnt work, and I've tried connecting to his brother's account (I'm friends with his brother and they live in the same house) and that doesn't work.
However, the only we can play together or connect in the same party is if we join another friend's party or game. He cannot host the party or game if there are other people in it though. So whats going on? I've played with him hundreds of times before these problems started happening, he lives 2 miles down the road from where I live, and we have had Live for years.
I'm not really technical so if the problem is complex please use simpler terms or please refer me to someone who can. It sucks not being able to play with your good friend. So it would mean a lot if you could help me with this problem. Thank You.
Oh yeah he has a Slim but he doesnt always play on it and I have an elite. I have a wired connection and I'm pretty sure he does too. I dont know if that is any helpful but I thought I'd post that.